Ass. Prof. Angelo ALL, MD MBA
Department of Biomedical Engineering
Department of Orthopedic Surgery
Department of Medicine, Division of Neurology
SINAPSE Institute
What ‘science’ is and how it works
BN4101 Research Methodology
Introductory lectures for final year students andfresh graduate students in the Faculty of Engineering
Aims
1. What is science and how it works
2. “The scientific method” and “methodological approaches”
3. Discriminate between “hypothesis”, “theory” & “laws”
The Scientific Cycle – the know How
What Science is and how it works
The pursuit of knowledge and understandingfrom the Latin term scientia, which means knowledge
The pursuit of knowledge and understandingfrom the Latin term scientia, which means knowledge
Science is: • a process for evaluating empirical and experimental knowledge• a global community of scholars, and the organized body of knowledge gained by this process and carried by this community (and others).
Science is: • a process for evaluating empirical and experimental knowledge• a global community of scholars, and the organized body of knowledge gained by this process and carried by this community (and others).
The Scientific Cycle – the know How
Content only is not Science
CONTENT
METHODOLOGY
CONTENT
Sum total of all facts, definitions, theories, techniques and relationships found in all of the individual scientific disciplines
This is what is usually taught in science text booksThis is what is usually taught in science text books
The Scientific Cycle – the know How
Methodology only is not Science
METHODOLOGY
Activity going on in the laboratories and fieldwork
Learning technologies and shopping for methods (“exposure”) does not make you a scientist Learning technologies and shopping for methods (“exposure”) does not make you a scientist
The Scientific Cycle – the know HowWhat Science is
CONTENT
METHODOLOGY
SCIENCE is Content and Methodology that are inseparably intertwined
Characteristics of Science
• Coherent understanding of observations
From Gregory N. Derrry’s book
• Growth and progress in understanding (ideas change over
time, reinterpretation in new light)
• Standing on the “shoulders of giants” , building on previous work, acknowledging it
• Rigorous logic, strict chain of deductive reasoning (ideally without gaps and weak spots)
• “Organised skepticism” (peer review, criticism and judgement to weed out bogus results
2. Research is..
Research is an active, diligent and systematic
process of inquiry
to
discover, interpret or revise
facts, events, behaviors, theories, or
to make practical applications
with the help of such facts, laws or theories
Research Methodology
Experimental• Chemical, biological, electrical, mechanical etc• Laboratory-based or field• Hands-on
Experimental• Chemical, biological, electrical, mechanical etc• Laboratory-based or field• Hands-on
Theoretical• Computer-based• Simulation, modeling, calculations• Link to actual data?
Theoretical• Computer-based• Simulation, modeling, calculations• Link to actual data?
Case studies• data and literature review
Case studies• data and literature review
4 steps of scientific Method
1. Observe some aspect of the universe
2. Invent a working assumption, called a hypothesis,
consistent with what you have observed
3. Use the hypothesis to make predictions
4. Test those predictions by experiments or further
observations, modify hypothesis in the light of your
results
Repeat steps 3 and 4 until there are no discrepancies between
theory and experiment and/or observation.
A Hypothesis is..
A limited statement regarding cause and effectin specific situations
It also refers to our state of knowledge before experimental work has been performed and perhaps even before new phenomena have been predicted
A hypothesis is a working assumption
Without a hypothesis you lack theintellectual basis for doing research
Advantage of the Scientific Method
• One does not have to believe a given researcher
• One can redo the experiment and determine whether his/her results are true or false
• The conclusions will hold irrespective of the state of mind, or the religious persuasion, or the state of consciousness of the investigator and/or the subject of the investigation
Faith, defined as belief that does not rest on logical proof or material evidence, does not determine whether a scientific theory is adopted or discarded
3. A scientific theory or law
• A hypothesis or a group of related hypotheses, which has been confirmed through repeated experimental tests
Theories in physics are often formulated in terms of a few concepts and equations, which are identified with "laws of nature," suggesting their universal applicability
Accepted scientific theories and laws become part of our understanding of the universe and the basis for exploring less well-understood areas of knowledge
Theories
”Theories are not easily discarded’’New discoveries are first assumed to fitInto the existing theoretical framework
It is only when, after repeated experimental tests,the new phenomenon cannot be accommodatedthat scientists seriously question the theory and attempt to modify it.
Testing hypotheses and Theories
• Experimental tests may lead either to the confirmation of the hypothesis or its ruling out
• A hypothesis has to be ruled out or modified if its predictions are clearly and repeatedly incompatible with experimental data
• Experiments may test the theory directly (for example, the observation of a new particle) or may test for consequences derived from the theory using mathematics and logic
• To be credible a theory must be testable, or even falsifiable
Common Mistakes
• Being BIAS
• Ignore Consensus backed by experimental results and acknowledged by members
of the scientific community
• To ignore or rule out data which do not support the hypothesis
• Failure to estimate quantitatively systematicerrors and all errors
Ockham's RazorWilliam of Ockham (14th century):
``Pluralitas non est ponenda sine neccesitate'',
``Multiplicity should not be placed without necessity”
If you have two theories, choose the one that is simpler, still explains the experimental data.
Observation: the street is wet
Its just a theory – or is it ?
A hypothesis is a working assumption.Typically, a scientist devises a hypothesis and then sees if it “holds water'' by testing it against available data (obtained from previous experiments and observations) If it does, the scientist declares it a theory. To a scientist a theory is a conceptual framework thatexplains existing observations and predicts new ones[Sun rise, gravity]
Truth and Proof in Science
Experiments sometimes produce results which
cannot be explained with existing theories
In this case it is the job of scientists to:• Produce new theories which replace the old ones• Explain all the observations and experiments the old
theory did and, in addition, the new set of facts
which lead to their development. • Define new theories (devour and assimilate old ones)• Repeatedly test existing theories in order to probe how
far they can be applied.
If scientific theories keep changing, where is the truth ?
When a theory is said to be “true'' it means that it agrees with all known experimental evidence.
When an accepted theory cannot explain some new data (which has been confirmed), the researchers strive to construct a new theory.
The new theory should not only explain the new data, but also all the old one.
Note: science does not make moral judgments,however, its conduct follows ethical rules.
Science Pseudoscience
• Growth and progress in understanding
• Coherent understanding of observations
• Rigorous logic and chain of reasoning
• “Organized skepticism” (peer review and criticism)
• Standing on the “shoulders of giants” - previous work
• Static (dogma, no changes)
• Randomly changing ideas
• Vague mechanisms to acquire understanding
• Loosely connected thoughts
• No tradition peer review
• Disregard of established results
• Closing down lines of enquiry
From Gregory N. Derrry’s book
A successful research design1- Hypothesis2- Aims3- Rational4- Innovation5- Significance6- Literature review7- Team members8- Materials and Methods9- Research plan10- Documentation11- Statistical analysis12- Interpretation13- Conclusion
Peer review evaluation
Modified from a Wikipedia text
scientists' manuscripts (or grant applications) are submitted by editors of scientific journals/grantors to anonymous fellow scientists familiar with the field for evaluation.
The referees may or may not recommend publication, publication with suggested modifications, or, sometimes, publication in another journal. This serves to keep the scientific literature free of unscientific or crackpot work, helps to cut down on obvious errors, and generally otherwise improve the quality of the scientific literature.
Sometimes peer review inhibits the circulation of unorthodox work, especially if it undermines the establishment in the particular field, and at other times may be too permissive. Other drawbacks includes cronyism and favoritism. Despite this, the peer review process is not always successful, but has been very widely adopted by the scientific community.
Review work is voluntarily given, without remuneration, as a matter of honor and service to the scientific community.
“Organised skepticism”
Documentation, reproducible and replicableThe data published must be comprehensive and complete. Consequently, it is a common practice for other scientists to attempt to repeat the experiments in order to duplicate the results.
ArchivingResearchers are expected to practice scientific data archiving in compliance with the policies of government funding agencies and scientific journals. Detailed records of their experimental procedures, raw data, statistical analyses and source code are preserved in order to provide evidence of the effectiveness and integrity of the procedure and assist in reproduction.
Furnishing the dataWhen additional information is needed before a study can be reproduced, the author of the study is expected to provide it promptly. If the author refuses to provide information, it is called data withholding
Some ReadingReferences
1. Wilson, E. Bright. An Introduction to Scientific Research (McGraw-Hill, 1952).2. Kuhn, Thomas. The Structure of Scientific Revolutions (Univ. of Chicago Press, 1962).3. Barrow, John. Theories of Everything (Oxford Univ. Press, 1991).4. Gregory N. Derry. What Science is and how it works (Princeton University Press 20025. E.Brian Davies. Science in the Looking Glass (Oxford University Press 2003)6. James Robert Brown. Who Rules in Science (Harvard University Press 2001)7. Terry Pratchett, Ian Stewart & Jack Cohen. The Science of Discworld III: Darwin’s Watch. Ebury Press 20058. Wikipedia, some unedited articles and chapters with further references